Historical information
Cooper S.E. Ball Bearing Grinder made and guaranteed by Sunbeam Corporation Limited. Grinders like this example have been made the same since the early 1900s, with this grinder thought to have been produced in the 1960s. It is belt driven, with the other end of the belt being attached to an engine; the same engine that would have powered the overhead shearing equipment in shearing sheds. It was common for shearing teams to bring their own equipment, especially pre-1960 as most shearing sheds were not connected to power, and shearers preferred to work with their own equipment. The engines that powered the shears and grinder were typically fuelled with kerosene or petrol. The large circular disks are attached to the bolt that protrudes from the grinder and fastened tightly with a nut. An example of seeing a similar grinder in action can be found on the following link - https://www.youtube.com/watch?v=O7eimI_Gm9o.
Inventor Frederick Wolseley made the world's first commercially successful power-shearing system in Australia in 1888. US company Cooper, which had been founded in 1843 as a maker of sheep dip, began selling Wolseley equipment in the USA in 1895. The Chicago Flexible Shaft Company successfully entered the power-shearing market a few years later and entered a joint venture with Cooper. It set up a branch in Sydney and sold shearing sets, and engines to power them, into the Australian market. In 1921 the US parent company, realising it needed to make products whose sales were not as seasonal as those of shearing equipment, made its first household appliances and branded them Sunbeam.
In 1933, changes in exchange rates and taxes led the company to manufacture engines and shearing equipment in Australia via subsidiary Cooper Engineering, which changed its name to Sunbeam in 1946. Although most Australians know of this company as a major manufacturer of household appliances, its rural division flourished and retained the Sunbeam name for shearing equipment even after it was taken over by New Zealand company Tru-Test in 2001.
Physical description
The grinder is formed from a central arch shaped block of green painted metal. Much of this paint has been lost to age, leaving the grinder in a ‘farm used’ condition with much surface oxidation present. On the front of the arch is a specification plate, reading “Cooper S.E. ball bearing grinder. Made and guaranteed by Sunbeam”. At the foot of the arch, three bolt holes are found for securing the grinder to the base of a solid wooden surface. Two of the bolt holes are found on the front of the grinder, with another found on the rear.
From the central arch, a bolt protrudes to the right of the grinder. This large bolt is for securing a grinding plate to the grinder.
Above the central arch is a pendulum which holds the comb / cutter that is being sharpened. From the pendulum, a large arm extends down (not pictured) to meet and strike the plate spinning at a rapid speed.
On the left-hand side of the central arch of the grinder, a wheel is found which a belt is attached to for power. This belt is then attached to a separate engine, spinning the wheel and hence powering the grinder. The wheel is partially covered with a section of protective bent tube, designed to provide protection from the rapidly spinning wheel. Below this wheel is the belt shifter. It is designed to move the protective bent tube from one side of the grinder to the other, to accommodate the grinder in the setup of different shearing sheds.
The two separate grinding plates are identical. They have a slight slope for sharpening the comb and cutters in the correct method, with a slight bias towards the base, or “tooth”, of the equipment. The disks have a large central bolt for attaching to the grinder. They have tags on the horizontal axis of the grinding plates, for securing the plates in transportation, and to help with initial alignment when setting up the grinder. The reverse of these grinding plates has the same green painted metal finish found on the grinder. This paint is also in a ‘farm used’ condition, with surface oxidation present.
The grinder would be provided from the factory with a comb holder, shifter for securing the grinding plates, emery cloth and emery glue. The emery cloth is what does the actual grinding and is applied to the grinding disks, replacing once well worn. These items can be seen in the final images in the multimedia section, showcasing advertising for this grinder.
Inscriptions & markings
Plate. Inscribed.
“Cooper /
S.E. BALL BEARING GRINDER /
MADE AND GUARANTEED BY /
Sunbeam /
CORPORATION LIMITED /
SYDNEY MELBOURNE /
ADELAIDE BRISBANE ”
